Zein, a prolamin protein in corn, is a unique biodegradable polymer that is found in abundance in corn gluten meal, a coproduct of corn wet milling. Zein exhibits hydrophobicity and thermoplastic behavior, which allows the natural polymer to be formed into films and coatings. Approved by U.S. Food and Drug Administration as a nontoxic material for food applications, zein is also biocompatible.
Petroleum-based polymer and plastic materials, such as poly(dimethylsiloxane) (PDMS), acrylics and polycarbonate, have been widely used to make mesoscale and microscale fluidic devices. A drawback of such microfluidic platforms is potential environmental pollution, especially when the devices are intended for use in the field for disposable applications.